[FFmpeg-devel] [PATCH] tests/checkasm/sw_rgb: don't write random data past the end of the buffer

[Ramiro Polla]

On Thu, Sep 12, 2024 at 4:44 PM James Almer <jamrial at gmail.com> wrote:
> On 9/12/2024 5:16 AM, Ramiro Polla wrote:
> > On Thu, Sep 12, 2024 at 8:44 AM James Almer <jamrial at gmail.com> wrote:
> >>
> >> Should fix fate-checkasm-sw_rgb under gcc-ubsan.
> >>
> >> Signed-off-by: James Almer <jamrial at gmail.com>
> >> ---
> >>   tests/checkasm/sw_rgb.c | 2 +-
> >>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/tests/checkasm/sw_rgb.c b/tests/checkasm/sw_rgb.c
> >> index af9434073a..cdd43df8ba 100644
> >> --- a/tests/checkasm/sw_rgb.c
> >> +++ b/tests/checkasm/sw_rgb.c
> >> @@ -287,7 +287,7 @@ static void check_deinterleave_bytes(void)
> >>                          int width, int height, int srcStride,
> >>                          int dst1Stride, int dst2Stride);
> >>
> >> -    randomize_buffers(src, 2*MAX_STRIDE*MAX_HEIGHT+2);
> >> +    randomize_buffers(src, 2*MAX_STRIDE*MAX_HEIGHT);
> >
> > Thank you for spotting it.
> >
> > The issue is that randomize_buffers() writes 4 bytes at a time. I
> > think the proper fix is to change randomize_buffers() to not write
> > past the end of the buffer. It would be even better to move
>
> 2*MAX_STRIDE*MAX_HEIGHT is a multiple of 4 and the exact size of the
> available buffer, whereas 2*MAX_STRIDE*MAX_HEIGHT+2 isn't.

Ok.